1 files changed, 32 insertions, 0 deletions
diff --git a/spec/ruby/library/matrix/unitary_spec.rb b/spec/ruby/library/matrix/unitary_spec.rb
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+++ b/spec/ruby/library/matrix/unitary_spec.rb
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+require_relative '../../spec_helper'
+
+require 'matrix'
+
+describe "Matrix.unitary?" do
+  it "returns false for non unitary matrices" do
+    Matrix[[0, 1], [1, 2]].should_not.unitary?
+    Matrix[[0, Complex(0, 2)], [Complex(0, 2), 0]].should_not.unitary?
+    Matrix[[1, 1, 0], [0, 1, 1], [1, 0, 1]].should_not.unitary?
+  end
+
+  it "returns true for unitary matrices" do
+    Matrix[[0, Complex(0, 1)], [Complex(0, 1), 0]].should.unitary?
+  end
+
+  it "returns true for unitary matrices with a Complex and a negative #imag" do
+    Matrix[[0, Complex(0, 1)], [Complex(0, -1), 0]].should.unitary?
+  end
+
+  it "raises an error for rectangular matrices" do
+    [
+      Matrix[[0], [0]],
+      Matrix[[0, 0]],
+      Matrix.empty(0, 2),
+      Matrix.empty(2, 0),
+    ].each do |rectangular_matrix|
+      -> {
+        rectangular_matrix.unitary?
+      }.should.raise(Matrix::ErrDimensionMismatch)
+    end
+  end
+end